.example-enter {
    opacity: 0.01;
    transition: opacity 1s ease-in;
}
.example-enter.example-enter-active {
    opacity: 1;
}
.example-leave {
    opacity: 1;
    transition: opacity 1s ease-in;
}
.example-leave.example-leave-active {
    opacity: 0.01;
}